No spark

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xskaternickx

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I'm trying to get my new to me 70' dart 318/904 to start but it's not getting any spark. Is there anything particular to check? I've fiddled with just about everything I can think of. Fuses, ballaster, coil, distributer cap and traced most of the wires. It's getting gas, and cranks fine but it isn't even trying to start...obviously since it's not getting any spark. I am sure it's something stupid that I'm missing like a ground or short but just thought I'd check to see what you guys have to say.
 
Have you jumped the ballast resistor?
 
Take off dist cap, put key in run position.
With the distibutor cam positioned so the points are closed, use a small screwdriver to lift the points open and let them drop back closed, and repeat.
You should see a small spark wgen you pull the points open.
Pull the wire out of the center of the distributor and lay it close to the block, or anything grounded.
Lift the points open again, and a spark should jump off the wire to the block.
If not, put a jumper wire across the ballast resistor and try again.
Get back to us with results.
 
I haven't tried jumping the ballast resistor. I switched it out with a new one and one off my satellite that I knew worked, But I didnt jump it. Do I leave it plugged in and just connect a wire across or take it off? I'll get back to you tomorrow with the results.
 
xskaternickx said:
I haven't tried jumping the ballast resistor. I switched it out with a new one and one off my satellite that I knew worked, But I didnt jump it. Do I leave it plugged in and just connect a wire across or take it off? I'll get back to you tomorrow with the results.
Click to expand...
Leave in the known good one in for now.
If you can get an assistant, watch the points as they crank to see if there's any spark at the points. The ballast resistor gets bypassed anyway by the igniton switch during cranking. Even if you do see a spark at the points, it could be a failed condenser.
In fact, if the condenser is failed the spark at the points will be too pronounced. When condenser is good, it's just a small spark at the points. A big spark means the energy which should be kicking the coil is jumping back and NOT building a field in the coil.
 
I'll get back to you later today when I have a extra hand to test it out.

AJ/FormS said:
Is this a "no start" or a "no spark"
For a no-start;
Did you verify that the dizzy is in the right way; that the rotor is under the #1 tower with the #1 piston at TDC-Compression?
Click to expand...
All that is happening right now is the starter is turning the engine over. Its not even trying to run, zero noise other than the starter. We determined it wasn't getting spark so we pulled a spark plug and tried to see if it would jump spark to ground but aren't getting anything.
 
Better to pull the coil wire;8 times as many sparks, makes lotsa noise;don't set your car on fire!

Points type systems are the simplest of all to diagnose, you will have it running in no time.

Having the dizzy installed wrong will not affect the sparking; rather, only a no-start.The spark would be there regardless of dizzy installed position.
 
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Sorry it took me a few days to get to it but I just came in from messing with the dart. I tried what you all suggested and my results are nada. I Switched out the coil with my old working one just for giggles even and didn't get any spark from the coil plug and obviously nothing at the points. Another issue is there's no power inside either. The only thing that's working is the horn and alt gauge. The fuse box is somewhat rusty and may be an issue.

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Open the points and stick a piece of paper or matchbook cover between the two contacts.
With that done do you have any power at that cracked wire on the coil with the key in the on position?
(like with a test light)
 
Well I don't know for sure but I don't think anything worked when I got it I just never noticed because the headliner and bulbs gone. But now that I'm tinkering around i noticed the radio and other interior lights aren't coming on either. The headlights do work. And it is still cranking.
Sorry didn't see the rest of your post. I will try that next
 
You need to figure if you have several things

1....Must have power to the coil when cranking. "Rig" your meter to the coil+ and watch the meter while cranking the engine USE THE KEY to do so, do not jumper the starter relay. You should have within a couple of tenths of a volt as 'same as battery.'. So after you read the coil+ / cranking, measure at the battery terminals. You want at least 10V or more

2....You have "sort of" determined the coil is good, as you switched the coil

3....If you do NOT have voltage to the coil, you can simply jumper a clip lead to a battery source, like the alternator output stud. DO NOT leave this hooked up longer than needed, you can damage the points and even the coil

4...After you get 1---3 above, determine if the points are conducting when closed, and opening. Turn the key to "run." Bump the engine round until the points are CLOSED. Measure both coil+ and coil --. You should have very LOW voltage at coil neg, and about 6--9 at coil POS

If you have this,.......

Bump the engine until the points are visibly open, and re-check. You should have "battery" at BOTH coil NEG and at coil POS

If you have this, chance the internal condenser (capacitor) inside the distributor.

5....I don't even use a feeler to set points. You can set them "on the starter" with a dwell meter. If you DO use a feeler, make sure you are careful, accurate, and that the feeler is clean. "Wiggle" the distributor shaft, looking for play and wear in the shaft / bushings.

=========================================

There are all kinds of "tricks" you can use. Get yourself a spark tester. There are all sorts of these. Check for spark RIGHT at the coil tower, and do NOT use the coil wire "to start with." The coil wire ITSELF could be bad!!!!

This is the one I use, about 7 bucks

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"Rig" it into the coil tower and to ground, and crank the engine USING THE KEY. Watch for spark as you are cranking

If you have a good hot blue spark there, move to the coil wire. You can check the coil and plug wires with an ohmeter. The "old rule" was that they need to be less than 1000 ohms per foot. Modern wires are normally LESS

Inspect the cap and rotor for moisture, oil/ dirt/ debri, and spark damage, "carbon tracking". Remove the rotor and inspect for carbon tracking and "punch through" under the button in the center.
 
I'm still in the process of following your steps but so far here's where I'm at. Pos on coil was just shy of 10v...9.98 ish. Battery read 12.18. With piece of paper between points I got 10.28 on the cracked wire on pos.
 
That shows the distributor side that is from coil NEG to ground through the dist. is SHORTED to ground. Under the same conditions, remove the dist wire from coil NEG. Coil POS should then be "same as battery."

Here's how this works. Power (functionally) comes from battery/ harness / ignition switch, and to the ballast resistor, then to the coil POS. With the coil NEG grounded through the points, current flows, dragging the voltalge down through the ballast resistor.

To confirm this, with the points closed, measure again to check, both sides of coil, and both sides of ballast

"Normal" with points closed / key "in run" "key" side of ballast should be very close to same as battery

"Coil" side of ballast ---same as coil POS should be somewhat lower, 8V or so, and

Coil NEG should be very very low.

NOW with points "bumped" around open or blocked open, ALL the voltage test points mentioned should be right up to battery voltage.

If that happens, confirms the dist side is shorted. Examine the dist wire where it goes through the dist case. They can short there. More likely is a mistake at the points connection........wire touching ground, insulator broken, part of it missing, etc, allowing points to ground. it would be rare for a condenser to COMPLETELY short but it could be

And, you MUST have a good condenser to make spark
 
Ok so I removed the distributor wire from the coil NEG and the readings are still 10.20s at coil POS Does this mean a short is between the battery and coil POS?
I ran out of sunlight I'll try again tomorrow.
 
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